Abstract: The DS1875 features a pulse-width modulation (PWM) controller that can be used to control aDC-DC converter. The DC-DC converter can then be used to generate the high bias voltages necessaryfor avalanche photodiodes (APDs). This application note describes the operation of a boost converterthat uses the DS1875. Discussion covers the selection of the inductor and switching frequency, and theselection of components that improve the efficiency of the converter. Test data are presented.
上傳時間: 2013-10-26
上傳用戶:lyson
gfdg
標簽: 發射
上傳時間: 2013-10-31
上傳用戶:wl9454
下載后請修改文件擴展名為sch.體積和代碼都很小,集成電路(ic)全為貼片,祝各位有所啟發。 mcu:at89c4051 fm:tea5767 time:ds1302 temp:ds18b20
上傳時間: 2013-12-28
上傳用戶:xiaoyaa
數字控制的交流調速系統所選用的微處理器、功率器件及產生PWM波的方法是影響交流調速系統性能好壞的直接因素。在介紹了正弦脈寬調制(SPWM)技術的基礎上,設計了一種以8098單片機作為控制器,以智能功率模塊IPM為開關器件的變頻調速系統。通過軟件編程,產生正弦脈沖寬度調制波形來控制絕緣柵雙極晶體管的導通和關斷,從而達到控制異步電動機轉速的目的。實驗結果表明,該系統可調頻率調電壓,穩定度高,調速范圍寬,具有較強的實用價值 Abstract: AC variable speed with digital control systems used microprocessors, power devices and generate PWM wave is the direct factors of affecting the performance AC speed regulation system. On the basis of introducing the sinusoidal pulse width modulation (SPWM) technology,this paper designed variable speed system which used 8098 as a controller, intelligent power module IPM as switching device. Through software programming, resulting in sinusoidal pulse width modulation waveform to control the insulated gate bipolar transistor turn on and off, so as to achieve the purpose of speed control of induction motors. Experimental results show that the system can adjust frequency modulation voltage, high stability, wide speed range, has a strong practical value.
上傳時間: 2013-11-14
上傳用戶:ynwbosss
覆蓋8位至32位的統一結構的單片機。 Panasonic(松下)AM1(MN101)和AM3(MN103)系列單片機,對機器驅動用軟件和系統需求進行分析,基于全新的概念開發而成。是一種對8位和32位采用統一結構,面向C語言,同時實現經濟性和高速性的,高性能,低功耗的單片機。 Panasonic系列單片機做為高性能嵌入式控制器和多媒體裝置的關鍵器件,在同一開發環境中開發,廣泛應用于諸多領域。
上傳時間: 2013-11-15
上傳用戶:daoyue
MSP430系列單片機的電源電壓采用1.8~3.6V低電壓,RAM 數據保持方式下耗電僅0.1uA,活動模 式耗電250pA/MIPS(MIPS:每秒百萬條指令數),IO輸入端口的漏電流最大僅50nA。 MSP430系列單片機有獨特的時鐘系統設計,包括兩個不同的時鐘系統:基本時鐘系統和鎖頻環(FLL 和FLL+)時鐘系統或DCO 數字振蕩器時鐘系統。由時鐘系統產生CPU和各功能模塊所需的時鐘,并且這 些時鐘可以在指令的控制下打開或關閉,從而實現對總體功耗的控制。由于系統運行時使用的功能模塊不 同,即采用不同的工作模式,芯片的功耗有明顯的差異。在系統中共有種活動模式(AM)和5種低功耗模式 (LPM0~LPM4)。 另外,MSP430系列單片機采用矢量中斷,支持十多個中斷源,并可以任意嵌套。用中斷請求將CPU 喚醒只要6us,通過合理編程,既以降低系統功耗,又可以對外部事件請求作出快速響應。
上傳時間: 2014-12-01
上傳用戶:lbbyxmoran
FEATURES400 MSPS internal clock speedIntegrated 10-bit DAC32-bit tuning wordPhase noise ≤ –120 dBc/Hz @ 1 kHz offset (DAC output)Excellent dynamic performance>75 dB SFDR @ 160 MHz (±100 kHz offset) AOUTSerial I/O control1.8 V power supplySoftware and hardware controlled power-down48-lead TQFP/EP packageSupport for 5 V input levels on most digital inputsPLL REFCLK multiplier (4× to 20×)Internal oscillator; can be driven by a single crystalPhase modulation capabilityMultichip synchronization
上傳時間: 2014-12-04
上傳用戶:axin881314
HT6221發碼的接收原理及應用 HT6221 是Holtek 公司生產的多功能編碼芯片,采用PPM(Pulse Position Modulation)進行編碼
上傳時間: 2014-09-10
上傳用戶:AbuGe
PCA9634是一款通過I2C總線控制的8位LED驅動器,該驅動器特別為紅/綠/藍/琥珀(RGBA)色的混合應用進行了優化。每個LED輸出都有自己的8位分辨率(256級)固定頻率的獨立PWM控制器,該控制器運行在97KHz的頻率下,占空比可由0%到99.6%可調,用以將LED設置到一個特定的亮度值。除此之外,該驅動器還有一個8位分辨率(256級)的組PWM控制器,該控制器的工作頻率可以為固定的190Hz,也可以在24Hz和每10.73秒一次(約0.093Hz)之間調整,其占空比為0%到99.6%可調,用于使所有LED以同樣的值模糊(dim)或者閃爍。
上傳時間: 2013-12-20
上傳用戶:liaofamous
The PCA9670 provides general purpose remote I/O expansion for most microcontrollerfamilies via the two-line bidirectional bus (I2C-bus) and is a part of the Fast-mode Plusfamily.The PCA9670 is a drop-in upgrade for the PCF8574 providing higher Fast-mode Plus(Fm+) I2C-bus speeds (1 MHz versus 400 kHz) so that the output can support PWMdimming of LEDs, higher I2C-bus drive (30 mA versus 3 mA) so that many more devicescan be on the bus without the need for bus buffers, higher total package sink capacity(200 mA versus 100 mA) that supports having all 25 mA LEDs on at the same time andmore device addresses (64 versus 8) are available to allow many more devices on the buswithout address conflicts.
上傳時間: 2013-10-15
上傳用戶:stella2015